| Message ID | 1468871491-10997-4-git-send-email-mathieu.poirier@linaro.org |
|---|---|
| State | New |
| Headers | show |
On 20 July 2016 at 10:07, Suzuki K Poulose <Suzuki.Poulose@arm.com> wrote: > On 18/07/16 20:51, Mathieu Poirier wrote: >> >> This patch implements the required API needed to access >> and retrieve range and start/stop filters from the perf core. >> >> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> >> --- >> drivers/hwtracing/coresight/coresight-etm-perf.c | 146 >> ++++++++++++++++++++--- >> drivers/hwtracing/coresight/coresight-etm-perf.h | 32 +++++ >> 2 files changed, 162 insertions(+), 16 deletions(-) >> >> diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c >> b/drivers/hwtracing/coresight/coresight-etm-perf.c >> index 78a1bc0013a2..fde7f42149c5 100644 >> --- a/drivers/hwtracing/coresight/coresight-etm-perf.c >> +++ b/drivers/hwtracing/coresight/coresight-etm-perf.c >> @@ -29,6 +29,7 @@ >> #include <linux/workqueue.h> >> >> #include "coresight-priv.h" >> +#include "coresight-etm-perf.h" >> >> static struct pmu etm_pmu; >> static bool etm_perf_up; >> @@ -83,12 +84,44 @@ static const struct attribute_group >> *etm_pmu_attr_groups[] = { >> >> static void etm_event_read(struct perf_event *event) {} >> >> +static int etm_addr_filters_alloc(struct perf_event *event) >> +{ > > > ... > >> + return 0; >> +} >> + > > > >> + >> static int etm_event_init(struct perf_event *event) >> { >> + int ret; >> + >> if (event->attr.type != etm_pmu.type) >> return -ENOENT; >> >> - return 0; >> + ret = etm_addr_filters_alloc(event); > > > >> } >> >> static void free_event_data(struct work_struct *work) >> @@ -456,6 +489,85 @@ static void etm_free_drv_configs(struct perf_event >> *event) >> } >> } >> >> +static int etm_addr_filters_validate(struct list_head *filters) >> +{ > > >> + >> + return 0; >> +} >> + >> +static void etm_addr_filters_sync(struct perf_event *event) >> +{ >> + struct perf_addr_filters_head *head = >> perf_event_addr_filters(event); >> + unsigned long start, stop, *offs = event->addr_filters_offs; >> + struct etm_filters *filters = event->hw.addr_filters; >> + struct perf_addr_filter *filter; >> + int i = 0; > > > Is it possible to delay the etm_addr_filters_alloc() until this point ? > I understand that this function cannot report back failures if we fail > to allocate memory. Or may be do a lazy allocation from > addr_filters_validate(), > when we get the first filter added. Humm... You want to avoid allocating memory that may never be used if filters aren't specified. Ok, let's do the allocation in addr_filters_validate(). > > Of course this could be done as a follow up patch to improve things once > we get the initial framework in. > > > >> + >> + list_for_each_entry(filter, &head->list, entry) { >> + start = filter->offset + offs[i]; >> + stop = start + filter->size; >> + >> + if (filter->range == 1) { >> + filters->filter[i].start_addr = start; >> + filters->filter[i].stop_addr = stop; >> + filters->filter[i].type = ETM_ADDR_TYPE_RANGE; >> + } else { >> + if (filter->filter == 1) { >> + filters->filter[i].start_addr = start; >> + filters->filter[i].type = >> ETM_ADDR_TYPE_START; >> + } else { >> + filters->filter[i].stop_addr = stop; >> + filters->filter[i].type = >> ETM_ADDR_TYPE_STOP; >> + } >> + } >> + i++; >> + } >> + >> + filters->nr_filters = i; >> +/** >> + * struct etm_filters - set of filters for a session >> + * @etm_filter: All the filters for this session. >> + * @nr_filters: Number of filters >> + * @ssstatus: Status of the start/stop logic. >> + */ >> +struct etm_filters { >> + struct etm_filter filter[ETM_ADDR_CMP_MAX]; > > > nit: having the variable renamed to etm_filter will make the code a bit more > readable > where we populate/validate the filters. Very well. Thanks, Mathieu > > Otherwise looks good > > Suzuki
On 21 July 2016 at 09:15, Mathieu Poirier <mathieu.poirier@linaro.org> wrote: > On 20 July 2016 at 10:07, Suzuki K Poulose <Suzuki.Poulose@arm.com> wrote: >> On 18/07/16 20:51, Mathieu Poirier wrote: >>> >>> This patch implements the required API needed to access >>> and retrieve range and start/stop filters from the perf core. >>> >>> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> >>> --- >>> drivers/hwtracing/coresight/coresight-etm-perf.c | 146 >>> ++++++++++++++++++++--- >>> drivers/hwtracing/coresight/coresight-etm-perf.h | 32 +++++ >>> 2 files changed, 162 insertions(+), 16 deletions(-) >>> >>> diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c >>> b/drivers/hwtracing/coresight/coresight-etm-perf.c >>> index 78a1bc0013a2..fde7f42149c5 100644 >>> --- a/drivers/hwtracing/coresight/coresight-etm-perf.c >>> +++ b/drivers/hwtracing/coresight/coresight-etm-perf.c >>> @@ -29,6 +29,7 @@ >>> #include <linux/workqueue.h> >>> >>> #include "coresight-priv.h" >>> +#include "coresight-etm-perf.h" >>> >>> static struct pmu etm_pmu; >>> static bool etm_perf_up; >>> @@ -83,12 +84,44 @@ static const struct attribute_group >>> *etm_pmu_attr_groups[] = { >>> >>> static void etm_event_read(struct perf_event *event) {} >>> >>> +static int etm_addr_filters_alloc(struct perf_event *event) >>> +{ >> >> >> ... >> >>> + return 0; >>> +} >>> + >> >> >> >>> + >>> static int etm_event_init(struct perf_event *event) >>> { >>> + int ret; >>> + >>> if (event->attr.type != etm_pmu.type) >>> return -ENOENT; >>> >>> - return 0; >>> + ret = etm_addr_filters_alloc(event); >> >> >> >>> } >>> >>> static void free_event_data(struct work_struct *work) >>> @@ -456,6 +489,85 @@ static void etm_free_drv_configs(struct perf_event >>> *event) >>> } >>> } >>> >>> +static int etm_addr_filters_validate(struct list_head *filters) >>> +{ >> >> >>> + >>> + return 0; >>> +} >>> + >>> +static void etm_addr_filters_sync(struct perf_event *event) >>> +{ >>> + struct perf_addr_filters_head *head = >>> perf_event_addr_filters(event); >>> + unsigned long start, stop, *offs = event->addr_filters_offs; >>> + struct etm_filters *filters = event->hw.addr_filters; >>> + struct perf_addr_filter *filter; >>> + int i = 0; >> >> >> Is it possible to delay the etm_addr_filters_alloc() until this point ? >> I understand that this function cannot report back failures if we fail >> to allocate memory. Or may be do a lazy allocation from >> addr_filters_validate(), >> when we get the first filter added. > > Humm... You want to avoid allocating memory that may never be used if > filters aren't specified. Ok, let's do the allocation in > addr_filters_validate(). > On second thought we don't have access to the perf event in addr_filters_validate() so the previous strategy won't work. And as you said etm_addr_filters_sync() doesn't return an error code so that won't work either. As such I will keep the current code as is. Mathieu >> >> Of course this could be done as a follow up patch to improve things once >> we get the initial framework in. >> >> >> >>> + >>> + list_for_each_entry(filter, &head->list, entry) { >>> + start = filter->offset + offs[i]; >>> + stop = start + filter->size; >>> + >>> + if (filter->range == 1) { >>> + filters->filter[i].start_addr = start; >>> + filters->filter[i].stop_addr = stop; >>> + filters->filter[i].type = ETM_ADDR_TYPE_RANGE; >>> + } else { >>> + if (filter->filter == 1) { >>> + filters->filter[i].start_addr = start; >>> + filters->filter[i].type = >>> ETM_ADDR_TYPE_START; >>> + } else { >>> + filters->filter[i].stop_addr = stop; >>> + filters->filter[i].type = >>> ETM_ADDR_TYPE_STOP; >>> + } >>> + } >>> + i++; >>> + } >>> + >>> + filters->nr_filters = i; >>> +/** >>> + * struct etm_filters - set of filters for a session >>> + * @etm_filter: All the filters for this session. >>> + * @nr_filters: Number of filters >>> + * @ssstatus: Status of the start/stop logic. >>> + */ >>> +struct etm_filters { >>> + struct etm_filter filter[ETM_ADDR_CMP_MAX]; >> >> >> nit: having the variable renamed to etm_filter will make the code a bit more >> readable >> where we populate/validate the filters. > > Very well. > > Thanks, > Mathieu > >> >> Otherwise looks good >> >> Suzuki
diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c index 78a1bc0013a2..fde7f42149c5 100644 --- a/drivers/hwtracing/coresight/coresight-etm-perf.c +++ b/drivers/hwtracing/coresight/coresight-etm-perf.c @@ -29,6 +29,7 @@ #include <linux/workqueue.h> #include "coresight-priv.h" +#include "coresight-etm-perf.h" static struct pmu etm_pmu; static bool etm_perf_up; @@ -83,12 +84,44 @@ static const struct attribute_group *etm_pmu_attr_groups[] = { static void etm_event_read(struct perf_event *event) {} +static int etm_addr_filters_alloc(struct perf_event *event) +{ + struct etm_filters *filters; + int node = event->cpu == -1 ? -1 : cpu_to_node(event->cpu); + + filters = kzalloc_node(sizeof(struct etm_filters), GFP_KERNEL, node); + if (!filters) + return -ENOMEM; + + if (event->parent) + memcpy(filters, event->parent->hw.addr_filters, + sizeof(*filters)); + + event->hw.addr_filters = filters; + + return 0; +} + +static void etm_event_destroy(struct perf_event *event) +{ + kfree(event->hw.addr_filters); + event->hw.addr_filters = NULL; +} + static int etm_event_init(struct perf_event *event) { + int ret; + if (event->attr.type != etm_pmu.type) return -ENOENT; - return 0; + ret = etm_addr_filters_alloc(event); + if (ret) + return ret; + + event->destroy = etm_event_destroy; + + return ret; } static void free_event_data(struct work_struct *work) @@ -456,6 +489,85 @@ static void etm_free_drv_configs(struct perf_event *event) } } +static int etm_addr_filters_validate(struct list_head *filters) +{ + bool range = false, address = false; + int index = 0; + struct perf_addr_filter *filter; + + list_for_each_entry(filter, filters, entry) { + /* + * No need to go further if there's no more + * room for filters. + */ + if (++index > ETM_ADDR_CMP_MAX) + return -EOPNOTSUPP; + + /* + * As taken from the struct perf_addr_filter documentation: + * @range: 1: range, 0: address + * + * At this time we don't allow range and start/stop filtering + * to cohabitate, they have to be mutually exclusive. + */ + if ((filter->range == 1) && address) + return -EOPNOTSUPP; + + if ((filter->range == 0) && range) + return -EOPNOTSUPP; + + /* + * For range filtering, the second address in the address + * range comparator needs to be higher than the first. + * Invalid otherwise. + */ + if (filter->range && filter->size == 0) + return -EINVAL; + + /* + * Everything checks out with this filter, record what we've + * received before moving on to the next one. + */ + if (filter->range) + range = true; + else + address = true; + } + + return 0; +} + +static void etm_addr_filters_sync(struct perf_event *event) +{ + struct perf_addr_filters_head *head = perf_event_addr_filters(event); + unsigned long start, stop, *offs = event->addr_filters_offs; + struct etm_filters *filters = event->hw.addr_filters; + struct perf_addr_filter *filter; + int i = 0; + + list_for_each_entry(filter, &head->list, entry) { + start = filter->offset + offs[i]; + stop = start + filter->size; + + if (filter->range == 1) { + filters->filter[i].start_addr = start; + filters->filter[i].stop_addr = stop; + filters->filter[i].type = ETM_ADDR_TYPE_RANGE; + } else { + if (filter->filter == 1) { + filters->filter[i].start_addr = start; + filters->filter[i].type = ETM_ADDR_TYPE_START; + } else { + filters->filter[i].stop_addr = stop; + filters->filter[i].type = ETM_ADDR_TYPE_STOP; + } + } + i++; + } + + filters->nr_filters = i; +} + int etm_perf_symlink(struct coresight_device *csdev, bool link) { char entry[sizeof("cpu9999999")]; @@ -485,21 +597,23 @@ static int __init etm_perf_init(void) { int ret; - etm_pmu.capabilities = PERF_PMU_CAP_EXCLUSIVE; - - etm_pmu.attr_groups = etm_pmu_attr_groups; - etm_pmu.task_ctx_nr = perf_sw_context; - etm_pmu.read = etm_event_read; - etm_pmu.event_init = etm_event_init; - etm_pmu.setup_aux = etm_setup_aux; - etm_pmu.free_aux = etm_free_aux; - etm_pmu.start = etm_event_start; - etm_pmu.stop = etm_event_stop; - etm_pmu.add = etm_event_add; - etm_pmu.del = etm_event_del; - etm_pmu.get_drv_configs = etm_get_drv_configs; - etm_pmu.free_drv_configs - = etm_free_drv_configs; + etm_pmu.capabilities = PERF_PMU_CAP_EXCLUSIVE; + + etm_pmu.attr_groups = etm_pmu_attr_groups; + etm_pmu.task_ctx_nr = perf_sw_context; + etm_pmu.read = etm_event_read; + etm_pmu.event_init = etm_event_init; + etm_pmu.setup_aux = etm_setup_aux; + etm_pmu.free_aux = etm_free_aux; + etm_pmu.start = etm_event_start; + etm_pmu.stop = etm_event_stop; + etm_pmu.add = etm_event_add; + etm_pmu.del = etm_event_del; + etm_pmu.get_drv_configs = etm_get_drv_configs; + etm_pmu.free_drv_configs = etm_free_drv_configs; + etm_pmu.addr_filters_sync = etm_addr_filters_sync; + etm_pmu.addr_filters_validate = etm_addr_filters_validate; + etm_pmu.nr_addr_filters = ETM_ADDR_CMP_MAX; ret = perf_pmu_register(&etm_pmu, CORESIGHT_ETM_PMU_NAME, -1); if (ret == 0) diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.h b/drivers/hwtracing/coresight/coresight-etm-perf.h index 87f5a134eb6f..28be38a9be60 100644 --- a/drivers/hwtracing/coresight/coresight-etm-perf.h +++ b/drivers/hwtracing/coresight/coresight-etm-perf.h @@ -20,6 +20,38 @@ struct coresight_device; +/* + * In both ETMv3 and v4 the maximum number of address comparator implentable + * is 8. The actual number is implementation specific and will be checked + * when filters are applied. + */ +#define ETM_ADDR_CMP_MAX 8 + +/** + * struct etm_filter - single instruction range or start/stop configuration. + * @start_addr: The address to start tracing on. + * @stop_addr: The address to stop tracing on. + * @type: Is this a range or start/stop filter. + */ +struct etm_filter { + unsigned long start_addr; + unsigned long stop_addr; + enum etm_addr_type type; +}; + +/** + * struct etm_filters - set of filters for a session + * @etm_filter: All the filters for this session. + * @nr_filters: Number of filters + * @ssstatus: Status of the start/stop logic. + */ +struct etm_filters { + struct etm_filter filter[ETM_ADDR_CMP_MAX]; + unsigned int nr_filters; + bool ssstatus; +}; + + #ifdef CONFIG_CORESIGHT int etm_perf_symlink(struct coresight_device *csdev, bool link);
This patch implements the required API needed to access and retrieve range and start/stop filters from the perf core. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> --- drivers/hwtracing/coresight/coresight-etm-perf.c | 146 ++++++++++++++++++++--- drivers/hwtracing/coresight/coresight-etm-perf.h | 32 +++++ 2 files changed, 162 insertions(+), 16 deletions(-) -- 2.7.4